This invention relates to a water purifier that preferably uses copper and silver ions to purify water, the copper ions destroying algae and the silver ions destroying bacteria.
The use of these beneficial minerals dates back centuries to the early ages of the Greeks and Romans, who used copper and silver coins in their water containers to keep their water potable. In more recent history, the pioneers trekking across North America in their covered wagons also used copper and silver coins in their oaken water casks. The copper and silver ions discharged by the coins killed the algae and bacteria, keeping the water potable during their long journey. They didn't know why, but it worked.
European countries have for many years been using copper and silver ions to control algae and bacteria in swimming pools and catchments with various crude devices using electric current passing between metal electrodes to discharge the ions into the water. In fact, there are some areas that prohibit the use of chlorine.
NASA developed further the use of copper and silver ions using low voltage direct current. At the present time, there are various ionization generators on the market, some complicated and costly, converting AC current to DC current and using metal rods placed in a pipe T fitting as electrodes. The pipe T would be placed in line with the water circulation pipes of swimming pool filter systems.
More recently offered on the market are flotation devices with photovoltaic cells attached to the top of the float and rods projecting from the bottom as electrodes. In some designs, one rod is composed of a copper/silver alloy and the opposing rod is of stainless steel. In other designs, a single copper/silver rod is surrounded by a metal coil or screen, acting as an opposing electrode.
Examples of the above devices and similar devices are disclosed in several U.S. patents.
U.S. Pat. No. 4,337,136 to Dahlgren discloses a floating container having a pair of silver-copper alloy electrodes extending from the bottom. The container holds a battery which is connected in circuit with the electrodes through a timer switch and a current reversing switch.
U.S. Pat. No. 4,525,253 to Hayes discloses a purification cell having two electrodes containing copper, silver and nickel. The purification cell is connected in line with the filtering system of a swimming pool.
U.S. Pat. No. 4,236,990 to King discloses a treater for aerating a liquid having a pair of closely spaced circular electrode plates with an annular groove adjacent to the discharge periphery of the lower plate that pressurizes the water passing between the plates to cause the discharging liquid to assume an umbrella like configuration.
U.S. Pat. No. 4,710,282 to Chak discloses a device for silverizing running water containing a plurality of disk shaped electrodes, each of which has either peripheral or central openings, each of which also is tightly surrounded by a main housing so that the water repeatedly changes its direction as it flows through the openings.
U.S. Pat. No. 4,713,170 to Saibic discloses a substantially "T" shaped hollow pipe fitting with a cylindrical electrical anode and an electrical cathode assembly.
U.S. Pat. Nos. 4,328,084 and 4,263,114 to Shindell disclose an apparatus and method for the treatment of water by adding salt to make the water slightly conductive and by circulating the water through an electric field between a pair of electrode plates.
U.S. Pat. No. 4,492,618 to Eder discloses a method of disinfecting water by immersing electrodes of a copper-silver alloy in the water, applying a direct current source of alternating polarity to the electrodes and adding sodium persulfate to the water.
U.S. Pat. No. 4,525,272 to Henson discloses an electrochemical ionization system for purifying water.
U.S. Pat. No. 3,654,119 to White discloses an oligodynamic treatment of liquids by passing liquids over electrodes of a copper and silver alloy.
U.S. Pat. No. 4,769,119 to Grundler discloses a water ionizing device having three concentric electrodes, the center one of silver and the others of copper.
U.S. Pat. No. 3,458,414 to Crane discloses a swimming pool conditioner having an electrolytic cell and a chemical dispenser.
All of these prior devices present retrofitting or aesthetic problems. For example, the pipe T fitting devices require that the swimming pool filter system be adapted for a pipe T. Because of the electrical and plumbing expenses involved, these devices are costly to install. It is also costly, time consuming and inconvenient to inspect the condition of these rods as they wear and to replace the rods.
The flotation devices present an aesthethic problem because they are extremely obvious on the surface of the water.
Most of the above devices use rods for electrodes, which is relatively inefficient because of the relatively small effective area being exposed to the water.
Accordingly, there is a need for a device that can be easily and inexpensively retrofitted to existing swimming pools and yet will retain the advantages and overcome the disadvantages of the previously described systems.
It is therefore an object of this invention to provide a device for purifying water which can be easily retrofitted to existing swimming pool installations.
It is a still further object of this invention to provide such a device that is easily accessible for maintenance and is easily maintained by the user.
It is a still further object of this invention to provide such a device with efficiently configured electrodes so that the device may be made smaller.
It is still further object of this invention to provide such a device that reduces the amount of chlorine necessary to maintain the purity of the water.
It is a still further object of this invention to provide such a device that is simple in construction and easy and inexpensive to manufacture.
It is a still further object of this invention to provide such a device that is hidden from view and therefore does not interfere with the aesthetic appearance of a pool.
It is a still further object of this invention to provide such a device that can be adjusted for various factors, such as pool size, water composition, circulation system and others.